Rotary engine

ABSTRACT

A rotary engine or turbine which uses a pressurized gas to drive a rotor and thereby produce rotary motion. The turbine has a solid cylindrical shaped rotor containing a multiplicity of flutes formed around its periphery. It also has a unique porting arrangement which uniformly directs the gas onto the flutes through multiple inlet ports that are aligned with corresponding exhaust ports thereby utilizing the energy of the pressurized gas to the maximum extent.

United States Patent [191 Hedges July 10, 1973 4] ROTARY ENGINE2,786,647 3/1957 Romero 415/92 76 l t use In Ross Hed es P.O. B 32, 1men or i s Iowa g ox Primary Examiner-C. J. Husar Attorney-Haven E.Simmons, James C. Nemmers [22] Filed: May 22, 1972 et 3L [2!] Appl. No.:255,376 [57] ABSTRACT A rotary engine or turbine which uses apressurized gas 52 US. Cl. 415/92, 60/3944 t0 drive a rotor and byproduce rotary motion- 51 1m. (:1. Fold 1/00 The turbine has a Solidcylindrical shaped rotor {58} Field of Search 415/92, 85; raining amultiplicity of flutes formed around its P p 0 39 ery. It also has aunique porting arrangement which uniformly directs the gas onto theflutes through multi- 5 References Cited ple inlet ports that arealigned with corresponding ex- P hauSt ports thereby the energy thepressur- 716,047 12/1902 lngham 415/92 Zed gas to the maximum extent.1,068,596 7/1913 Long 415/92 11 Claims, 3 Drawing Figures Patented July10, 1973 3 Sheets-Sheet 1 Patent ed July 10,1973

. 3 Sheets-Sheet 3 ROTARY ENGINE BACKGROUND OF THE INVENTION There havebeen developed numerous designs of both internal combustion engines andturbines of a variety of types. Primarily because of its adverse effectson the environment, the internal conbustion engine, particularly thereciprocating piston engine, is falling into disfavor. Although theturbine engine appears to have some advantages over the internalcombustion engine as far as its effect on the environment, there has notbeen developed turbines which are of a practical design, low in cost andwhich can be used in low horsepower requirement applications.

There is also a considerable amount of controversy and growing concernabout large, central, power generating stations because of their largeconsumption of fossil fuels the supply of which is not inexhaustable.Also, the burning of fossil. fuel creates air pollution problemsparticularly in the quantities used by these large power plants. Some ofthese large plants are being replaced or supplemented with powergenerating stations which utilize nuclear reactors as a source of power.However, these also are somewhat controversial because of theirundetermined long range effect on the environment. It is notinconceivable that someday power can be generated by individualgenerating plants at each location where the power is desired. Such anapproach would not only eliminate the need for the large central powergenerating plants but it would also minimize the problems of powerdistribution. The use of independent individual generating plants alsohas many aesthetic advantages, such as the elimination of powertransmission lines, but to date this approach has not been practicalbecause of the unavailability of suitable power plants for eachindividual installation. If a small power generating unit were availablewhich had little or no effect on the environment, and if such agenerating plant could be provided at a reasonable cost, there would bemany advantages to using such plants.

Also, with the number of vehicles presently being used in the world allof which utilize internal combustion engines, the air pollution problemsare approaching a critical point. There is, therefore, a need for arelatively small horsepower unit which could be used in vehicles withoutthe adverse efiects on the environment that present day internalcombustion engines create.

SUMMARY OF THE INVENTION erly assembled provide a unique portingarrangement that allows the pressurized gas to be introduced through asingle port and uniformly distributed across the face of the rotor andagainst the flutes to produce the rotary motion. Also, the inlet andexhaust ports are uniquely designed so as to be in alignment therebyallowing the gas to travel in a direction that produces the maximumamount of torque for the energy supplied. Because of the way in whichthe turbine is constructed utilizing a plurality of annular shaped partsthat are concentrically arranged within a housing surrounding the rotor,the device is easy to manufacture and easy to service and maintain. Insmall horsepower applications, the turbine is a very efficient powerplant which can be manufactured at a relatively low cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective viewof a rotary motor constructed according to the principles of theinvention;

FIG. 2 is a sectional view taken along a diameter of the rotary motor;and

FIG. 3 is a sectional view taken along the line 3 3 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION The rotarymotor or turbine of my invention consists of relatively few parts mostof which are inside of a housing Ill which is cylindrical in shape andwhich contains an inlet port 12 communicating with a circumferentialgroove l4 formed in the inner surface 113 of the housing 10. Inaddition, housing 10 contains two exhaust ports 16 which communicatewith corresponding circumferential grooves 18 also formed in the innersurface 13 of the housing 10. As best seen in FIG. 1, grooves 14 and 18are axially spaced apart with groove 14 being positioned between the twogrooves 18. Preferably, each of the grooves 14 and 18 is of a somewhatsemicircular cross sectional shape as best seen in FIG. 2. Receivedwithin the housing 10 is a first sleeve indicated generally by thereference numeral 20. Sleeve 20 has an outer surface 22 which engagesthe inner surface 13 of housing 10 when the two parts are assembled, andthe machining of housing 10 and sleeve 20 must be precise and withminimum tolerances so that surface 22 will provide a tight sealing fitagainst surface 33. Extending radially through the sleeve 20 from itsouter surface 22 to its inner surface 24 are a plurality of ports 26which are axially positioned so as to communicate with the groove 14 ofhousing 10. In the embodiment shown, there are four such ports 26 evenlyspaced circumferentially around the sleeve 20. Each of the ports 26communicates with an axially extending groove 28 formed along the innersurface 24. As best seen in FIG. 3, each groove 28 is preferablysemicircular in cross section and is uniform in dimension along itsentire length. Sleeve 20 has two additional sets of ports 30 each ofwhich extends through sleeve 20 from its outer surface 22 to the innersurface 24. Each set of ports 30 corresponds in axial position to one ofthe grooves T8 in the housing 10. In the embodiment shown, there arefour such ports 30 in each set and thus four such ports whichcommunicate with each of the grooves E8 in the housing 10.

Extending axially on the inside surface 24 of sleeve 20 there are inaddition to grooves 28 four grooves 32 each of which communicates withone of the ports 30 in each set of four ports. In order to accomplishthis communication between ports 30 and grooves 32 ports 30 arecircumferentially spaced from the ports 26 with one of the ports 30 ineach set being axially aligned with a corresponding port 30 in the otherset. Thus, with the sleeve 20 positioned inside of housing lltl andproperly aligned with respect thereto, fluid introduced into port 12 ofhousing will flow through the passageway provided by groove 14 and thenthrough each of the ports 26 into the passageways provided by grooves 28in the sleeve 20. Similarly, separate and independent paths for the flowof fluid are provided from grooves 32 in sleeve through ports 30 andinto the passageways provided by grooves 18 in housing 10 and thenthrough port 16 in housing 10.

In order to continue the unique porting arrangement, there is provided asecond sleeve indicated generally by reference numeral 34 which is alsoa hollow cylinder having an outer surface 36 and an inner surface 38.Formed in the outer surface 36 are four circumferentially spaced-apartaxially extending grooves 40 each of which is formed so as to correspondwith and be in alignment with a respective groove 28 in the first sleeve20. The outer diameter of the second sleeve 34 is only slightly lessthan the inner diameter of the first sleeve 20 so that when sleeve 20and 34 are assembled, the outer surface 36 of sleeve 34 will sealinglyengage the inner surface 24 of sleeve 20. The tolerances on themachining of these surfaces should be such that surface 36 of sleeve 34and surface 24 of sleeve 20 will provide a metal-to-metal seal. Formedin each of the grooves 40 are a plurality of axially spaced ports 42each of which extends through sleeve 34 to its inner surface 38.Similarly, axially extending grooves 44 are circumferentially spacedaround and formed in the outer surface 36 of sleeve 34. Grooves '44 arepositioned so as to correspond to the grooves 32 in the sleeve 20 whenthat sleeve is assembled with sleeve 34. Grooves 44 each have formedtherein a plurality of axially spaced ports 46 which extend throughsleeve 34 to its inner surface 38.

To complete the unique porting arrangement of the invention there isprovided a third sleeve indicated generally by the reference numeral 48.Sleeve 48 is also a hollow cylinder the outer diameter of which is justslightly less than the inner diameter of sleeve 34 so that when sleeves34 and 48 are assembled the outer surface 50 of sleeve 48 will engagethe inner surface 38 of sleeve 34 and provide a metal-to-metal seal. Asbest seen in FIG. 1, sleev 48 has four sets of axially spaced ports 52which extend through sleeve 48 from its outer surface 50 to its innersurface 54. The ports.52 in each set are positioned so as to correspondto and be in alignment with a set of ports 42 in sleeve 34 when the twosleeves are properly assembled in the unit. However, as best seen inFIG. 3, ports 52 do not extend along radial lines like ports 42, butrather extend along chordal lines of the cylindrical shaped sleeve 48.In addition to the four sets of ports 52, sleeve 48 is also providedwith four sets of axially spaced ports 56 which are positioned so as tobe in alignment with corresponding ports 46 in sleeve 34. Ports 56 alsoextend from the outer surface 50 to the inner surface 54 of sleeve 48but do not extend along radial lines. As shown in FIG. 3, respectiveones of ports 52 and 56 are in linear alignment along chordal lines. Theports 52 serve as inlet ports and because of their alignment, willdirect the pressurized fluid in a direction so as to produce maximumtorque on the rotor, which is indicated generally be the referencenumeral 58. Rotor 58 is preferably a inlet port 52 to produce rotationof the rotor 58. As best seen in FIG. 2, the flutes 60 are staggered in24 axial spaced sets of five flutes each, half the numer of inlet ports52 in each set of ten. By this arrangement, the number of impulses perrevolution of rotor 58 are doubled thus producing a smoother operatingmotor. From FIG. 3 it should be noted that four sets with five flutes 60in each set are in alignment with all four sets of inlet ports 52simultaneously, and at this time (the inlet cycle) none of the flutes 60are in alignment with the ports 56 which serve as exhaust ports.However, as the rotor 58 continues to rotate, the sets of flutes 60communicating with inlet ports 56 will move past the inlet ports 52 andthe sets of flutes 60 just ahead will come into communication with theexhaust ports 56. During this cycle, (the exhaust cycle), the flutes 60containing pressurized fluid are in between sets of ports, and they donot reach the exhaust ports 56 until another inlet cycle has occurredduring which the sets of five flutes 60 following are in communicationwith inlet ports 52. This arrangement provides for maximum utilizationof the available energy and provides for a continuously operating motoras long as pressurized fluid is supplied to the units.

Rotor 58 is mounted on a central shaft 64 one end of which 66 is seatedin a suitable bearing 68 that is retained in place by end plate 70. Ifdesired, a suitable seal 72 can be provided between rotor 58.and thebearing 68. A cover plate 74 completes the enclosure at one end of theunit and serves to retain the bearing 68 in position while providing acup 76 into which the end 66 of the shaft 64 extends. End cup 76 thusprovides an enclosure for a suitable lubricant. Both the end plate andcover plate 74 are held in place by suitable fastening means such asbolts 78 which are threaded into the main housing 10.

The other end 80 of shaft 64 is also supported by a bearing 82 held inplace by an end plate 84 with a seal 86 positioned between the bearing82 and the rotor 58. The end plate 84, similar to end plate 70, isconnected by suitable fastening means (not shown) to the other end ofthe main housing 10. The end 80 of shaft 64 of the rotor 58 provides anoutput shaft the rotating motion of which can be utilized to drive anysuitable device. If desired, end 80 of rotor shaft 64 can be used topower a power output shaft 88 which is connected to shaft 64 through aplanetary drive gear arrangement indicated generally by the referencenumeral 90. It should be understood that any suitable drive or geararrangement other than that shown in FIG. 1 can be utilized, theinvention residing in the construction and operation of the power unititself.

In operation, a power unit or turbine constructed according to theinvention is connected to a source of pressurized fluid. This might be,for example, a source of a heavy gas such as freon in which the turbinewould be part of a closed system recycling the same fluid through acondensing-heating cycle. Of course, the unit could also be driven bysteam with a minor modification to adapt the unit for steam. In eitherevent, the pressurized fluid is supplied to the unit through inlet port12 and distributed around the groove 14 and thence through ports 26 intothe axial grooves 28. The pressurized fluid then flows through ports 42into the inlet ports 52 from where it is simultaneously directed againstfour sets of five flutes 60 of rotor 58 causing the rotor to turn.

in FIG. 3 there are shown twelve of the 24 sets each set containing fiveflutes oil. The other 12 sets of flutes 60 are staggered as best seen inFIG. I.

For purposes of illustration, I have designated in FIG. 3 four of the 12sets of flutes shown as sets a, four more as sets I) and the other fouras sets c. The operation described hereafter is with reference to the 12sets shown, it being understood that simultaneously identical cycleswill be going on for the other 12 sets of flutes, each such cyclefollowing the described cycle by 15 of rotation of rotor 58. When rotor58 is in the position shown in FIG. 3, flutes a are in communicationwith the inlet ports 52, while flutes b and c are not in communicationwith any ports. As the rotor 58 continues to move, flutes a will moveout of communication with inlet ports 52 and flutes b will move intocommunication with exhaust ports 56. Flutes c are now between inletports 52 and exhaust ports 56. As flutes b complete their exhaust cycle,flutes 0 will be in their inlet cycle by moving into communication witinlet ports 52. When flutes b have completed their exhaust cycle, fultes0 will be completing their inlet cycle as flutes a start into theirexhaust cycle. With flutes a in the exhaust cycle, flutes b will starttheir inlet cycle upon completion of which cycles, flutes c will starttheir exhaust cycles and flutes a will move into another inlet cycle. Atthe end of each exhaust cycle, the exhaust fluid will flow through ports56 and out of ports 46 into the axial grooves 32 and then through ports30 into the grooves 18 of the main housing 10. The fluid is thenexhausted from the unit through the ports 16 where, in a closed system,the fluid would then be condensed, heated and reintroduced into inletport 112 of the unit.

During the foregoing described cycles when each set of flutes has movedthrough both an inlet and an exhaust cycle, the rotor 58 will havecompleted onefourth of a revolution. Thus, each of the 12 sets of flutes60, shown in FIG. 3, will go through a complete cycle four times duringa single revolution of the rotor 58. Since there are twelve additionalsets of flutes 60 simultaneously going through a complete cycle duringeach one-fourth of a revolution of rotor 58, during a single revolutionof rotor 58 there will occur 96 complete cycles with power beingproduced by five flutes 60 in each cycle. Thus, there will be a total of480 power impluses during a single revolution of rotor 53. This islargely responsible for the efficiency of the unit and its extremelysmooth operation.

From the foregoing description, it will be evident that the inlet fluidflows freely and uniformly from the time it is first introduced throughinlet port I2 until it is directed into the flutes 60 of rotor 58.Similarly, the exhaust fluid flows freely from the flutes 60 of rotor 58untii it is exhausted from the ports 16. This smooth uniform flow isprovided and distributed by means of the unique porting arrangementformed by proper assembly of the rotor 58 and the three sleeves 2t), 34and 48 into the main housing 10. Each of the component parts of the unitis designed so that it can be easily and accurately machined to closetolerances. Assembly of the unit is obviously easy to accomplish andlikewise the unit is easily disassembled when necessary. The unit has aminimum of moving parts, the rotor 58 and the unique arrangement of itsflutes 60 relative to the ports of sleeve 48 providing the necessaryinlet and exhaust functions at the properly timed intervals. There is,therefore, no necessity for troublesome inlet and exhaust valves withthe necessary mechanism to provide proper timing. Thus, the unit of theinvention is extremely simple and relatively easy to manufacture andassemble. The invention thus provides an efficient, relativelyinexpensive rotary motor with a number of uses particularly in low powerrequirements. For example, the unit would make an extremely efficient,quiet, and pollution free power unit for a small electrical generatingplant. The unit would be relatively maintenance free and because of itsrelatively low cost could be used in small electrical generating plantsfor individual residences. The unit, of course, can be made in varioussizes and power outputs and, thus, would have a broad range ofapplication.

Although I have described only a preferred embodiment of my invention,it will be evident to those skilled in the art that various revisionsand modifications can be made in this specific construction of theembodiment without departing from the spirit and scope of the invention.it is my intention, however, that all such revisions and modificationswhich are obvious to those skilled in the art will be included withinthe scope of the following claims.

I claim:

1. A rotary engine powered by pressurized fluid and comprising a housinghaving outer and inner surfaces and an inlet port and an exhaust porteach extending through said housing from said outer surface to saidinner surface, a first sleeve positioned within said housing and havinga plurality of inlet ports and a plurality of exhaust ports, first meansproviding communication between the inlet port of said housing and theinlet ports of said first sleeve and between the exhaust port of saidhousing and the exhaust ports of said first sleeve, a second sleevepositioned within first sleeve and having a plurality of inlet ports anda plurality of exhaust ports, second means providing communicationbetween the inlet ports of said first and second sleeves and between theexhaust ports of said first and second sleeves, a third sleevepositioned within said second sleeve and having a plurality of inletports and a plurality of exhaust ports, third means providingcommunication between inlet ports of said second and third sleeves andbetween the exhaust ports of said second and third sleeves, a rotorreceived within said third sleeve, means for rotatably supporting saidrotor within said housing, a power output shaft operatively connected tosaid rotor, and a plurality of flutes spaced around the periphery ofsaid rotor and positioned thereon so as to be in communcation atselected times with selected ones of the inlet and exhaust ports of saidthird sleeve, as said rotor rotates, the ports of said first, second andthird sleeves combined with said first, second and third means providingfor distribution of said pressurized fluid onto a plurality of some ofsaid flutes simultaneously and further providing 'for exhausting offluid from said flutes.

2. The rotary engine of claim I in which said first, second and thirdsleeves are each hollow cylinders with the respective ports in eachsleeve extending from the outer surface to the inner surface thereof.

3. The rotary engine of claim 2 in which both the inlet and exhaustports of said first sleeve are circumferentially spaced, and said firstmeans provides for flow of said pressurized fluid from said inlet portcircumferentially to all of the inlet ports in said first sleeve andfurther provides independently for flow of said pressurized fluid fromthe exhaust ports in said first sleeve circumferentially to the exhaustports in said housing, the inlet ports in said second sleeve beingaxially spaced apart in circumferentially spaced rows and the exhaustports in said second sleeve also being axially spaced part incircumferentially spaced rows, said second means providing for flow ofsaid fluid in an axial direction from the inlet ports in said firstsleeve to the inlet ports of said second sleeve and further providingfor flow of said pressurized fluid in an axial direction from theexhaust ports in second sleeve to the exhaust ports in said firstsleeve, the inlet ports in said third sleeve being axially spaced apartin circumferentially spaced rows, the exhaust ports in said third sleevebeing axially spaced apart in circumferentially spaced rows, and saidthird means providing for communication between respective ones of theinlet ports in said third sleeve and the inlet ports in said secondsleeve and the exhaust ports in said third sleeve and the exhaust portsin said second sleeve.

4. The rotary engine of claim 3 in which said first means includes aplurality of annular grooves formed on the inner surface of saidhousing, said annular grooves being axially spaced and positionedrelative to the inlet and exhaust ports of said housing and said firstsleeve so as to provide communication between the inlet ports andbetween the exhaust ports, said second means including axial groovesformed in the inner surface of said first sleeve and circumferentiallyspaced and positioned so as to provide communication between therespective inlet and exhaust ports of said first and second sleeves.

5. The rotary engine of claim 4 in which said flutes are axially spacedapart in circumferentially spaced rows around the periphery of saidrotor, the flutes in each row being off-set axially from the flutes inadjacent rows.

6. The rotary engine of claim 5 in which the inlet ports in a row ofinlet ports of said third sleeve are in alignment with respectiveexhaust ports in a row of exhaust ports in said third sleeve, saidalignment being along chordal lines, so that pressurized fluid flowsfrom an inlet port to an exhaust port through a flute on said rotor.

7. The rotary engine of claim 6 in which there are three times as manyflutes on said rotor as there are inlet ports in said third sleeve,one-half of said flutes being in alignment simultaneously with one-halfof said inlet ports in each row, the other half of said inlet ports andflutes being simultaneously in alignment at different times during acomplete revolution of said rotor.

8. The rotary engine of claim 7 in which said rotor is a solid cylinderand said flutes are formed in the peripheral surface thereof, each flutebeing triangular in cross-section.

9. The rotary engine of claim 1 in which each inlet port in said thirdsleeve is in alignment with a respective one of the exhaust ports insaid sleeve, each pair of inlet and exhaust ports being along a chordalline.

10. The rotary engine of claim 9 in which the flutes on said rotor areaxially spaced apart in circumferentially spaced rows around theperiphery of said rotor, the flutes in a row being off-set axially fromthe flutes in adjacent rows.

11. The rotary engine of claim 10 in which said rotor is a solidcylinder and the flutes are formed in the peripheral surface thereof,each flute being triangular in cross-section.

1. A rotary engine powered by pressurized fluid and comprising a housinghaving outer and inner surfaces and an inlet port and an exhaust porteach extending through said housing from said outer surface to saidinner surface, a first sleeve positioned within said housing and havinga plurality of inlet ports and a plurality of exhaust ports, first meansprovidiNg communication between the inlet port of said housing and theinlet ports of said first sleeve and between the exhaust port of saidhousing and the exhaust ports of said first sleeve, a second sleevepositioned within first sleeve and having a plurality of inlet ports anda plurality of exhaust ports, second means providing communicationbetween the inlet ports of said first and second sleeves and between theexhaust ports of said first and second sleeves, a third sleevepositioned within said second sleeve and having a plurality of inletports and a plurality of exhaust ports, third means providingcommunication between inlet ports of said second and third sleeves andbetween the exhaust ports of said second and third sleeves, a rotorreceived within said third sleeve, means for rotatably supporting saidrotor within said housing, a power output shaft operatively connected tosaid rotor, and a plurality of flutes spaced around the periphery ofsaid rotor and positioned thereon so as to be in communcation atselected times with selected ones of the inlet and exhaust ports of saidthird sleeve, as said rotor rotates, the ports of said first, second andthird sleeves combined with said first, second and third means providingfor distribution of said pressurized fluid onto a plurality of some ofsaid flutes simultaneously and further providing for exhausting of fluidfrom said flutes.
 2. The rotary engine of claim 1 in which said first,second and third sleeves are each hollow cylinders with the respectiveports in each sleeve extending from the outer surface to the innersurface thereof.
 3. The rotary engine of claim 2 in which both the inletand exhaust ports of said first sleeve are circumferentially spaced, andsaid first means provides for flow of said pressurized fluid from saidinlet port circumferentially to all of the inlet ports in said firstsleeve and further provides independently for flow of said pressurizedfluid from the exhaust ports in said first sleeve circumferentially tothe exhaust ports in said housing, the inlet ports in said second sleevebeing axially spaced apart in circumferentially spaced rows and theexhaust ports in said second sleeve also being axially spaced part incircumferentially spaced rows, said second means providing for flow ofsaid fluid in an axial direction from the inlet ports in said firstsleeve to the inlet ports of said second sleeve and further providingfor flow of said pressurized fluid in an axial direction from theexhaust ports in second sleeve to the exhaust ports in said firstsleeve, the inlet ports in said third sleeve being axially spaced apartin circumferentially spaced rows, the exhaust ports in said third sleevebeing axially spaced apart in circumferentially spaced rows, and saidthird means providing for communication between respective ones of theinlet ports in said third sleeve and the inlet ports in said secondsleeve and the exhaust ports in said third sleeve and the exhaust portsin said second sleeve.
 4. The rotary engine of claim 3 in which saidfirst means includes a plurality of annular grooves formed on the innersurface of said housing, said annular grooves being axially spaced andpositioned relative to the inlet and exhaust ports of said housing andsaid first sleeve so as to provide communication between the inlet portsand between the exhaust ports, said second means including axial groovesformed in the inner surface of said first sleeve and circumferentiallyspaced and positioned so as to provide communication between therespective inlet and exhaust ports of said first and second sleeves. 5.The rotary engine of claim 4 in which said flutes are axially spacedapart in circumferentially spaced rows around the periphery of saidrotor, the flutes in each row being off-set axially from the flutes inadjacent rows.
 6. The rotary engine of claim 5 in which the inlet portsin a row of inlet ports of said third sleeve are in alignment withrespective exhaust ports in a row of exhaust ports in said third sleeve,said alignment being along chordal lines, so that pressurized fluidflows from an inlet port to an exhaust port through a flute on saidrotor.
 7. The rotary engine of claim 6 in which there are three times asmany flutes on said rotor as there are inlet ports in said third sleeve,one-half of said flutes being in alignment simultaneously with one-halfof said inlet ports in each row, the other half of said inlet ports andflutes being simultaneously in alignment at different times during acomplete revolution of said rotor.
 8. The rotary engine of claim 7 inwhich said rotor is a solid cylinder and said flutes are formed in theperipheral surface thereof, each flute being triangular incross-section.
 9. The rotary engine of claim 1 in which each inlet portin said third sleeve is in alignment with a respective one of theexhaust ports in said sleeve, each pair of inlet and exhaust ports beingalong a chordal line.
 10. The rotary engine of claim 9 in which theflutes on said rotor are axially spaced apart in circumferentiallyspaced rows around the periphery of said rotor, the flutes in a rowbeing off-set axially from the flutes in adjacent rows.
 11. The rotaryengine of claim 10 in which said rotor is a solid cylinder and theflutes are formed in the peripheral surface thereof, each flute beingtriangular in cross-section.